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How to do a batch insert in MySQL
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From the MySQL manual
INSERT statements that use VALUES
syntax can insert multiple rows. To do
this, include multiple lists of column
values, each enclosed within
parentheses and separated by commas.
Example:
INSERT INTO...
“’” showing on page instead of “ ' ”
...set the encoding of the table when you create it.
You're most likely using SQL Server, but here is some MySQL code (copied from this article):
CREATE DATABASE db_name CHARACTER SET utf8;
CREATE TABLE tbl_name (...) CHARACTER SET utf8;
If your table is however already UTF-8, then you need to take a ...
If string is empty then return some default value
... is not empty.
For example
@user.address.or User.make_a_long_and_painful_SQL_query_here
would make extra work even if address is not empty. Maybe you could update that a bit (sorry about confusing one-liner, trying to keep it short):
class String
def or what = ""
self.strip.empty? ? block...
What is the maximum number of characters that nvarchar(MAX) will hold?
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From char and varchar (Transact-SQL)
varchar [ ( n | max ) ]
Variable-length, non-Unicode character
data. n can be a value from 1 through
8,000. max indicates that the
maximum storage size is 2^31-1 bytes.
The storage size is the actual length
of data ente...
What are '$$' used for in PL/pgSQL
Being completely new to PL/pgSQL , what is the meaning of double dollar signs in this function :
2 Answers
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What is “overhead”?
...(arguably more absurd) approach would be to post all of the inputs to some SQL table in an RDBMS. Then simply calling the SQL SUM function on that column of that table. This shifts our local memory overhead to some other server, and incurs network overhead and external dependencies on our executio...
postgresql - add boolean column to table set default
Is this proper postgresql syntax to add a column to a table with a default value of false
5 Answers
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creating a random number using MYSQL
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pmin INTEGER,
pmax INTEGER
)
RETURNS INTEGER(11)
DETERMINISTIC
NO SQL
SQL SECURITY DEFINER
BEGIN
RETURN floor(pmin+RAND()*(pmax-pmin));
END;
and call like
SELECT myrandom(100,300);
This gives you random number between 100 and 300
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Close and Dispose - which to call?
Having read the threads Is SqlCommand.Dispose enough? and Closing and Disposing a WCF Service I am wondering for classes such as SqlConnection or one of the several classes inheriting from the Stream class does it matter if I close Dispose rather than Close?
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Escape single quote character for use in an SQLite query
...ng the backslash character are not supported because they are not standard SQL. BLOB literals are string literals containing hexadecimal data and preceded by a single "x" or "X" character. ... A literal value can also be the token "NULL".
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